Yarn feeding mechanism for knitting machines



J ly 17, 195 A. M. BROWN 2,561,175

YARN FEEDING MECHANISM FOR KNITTING MACHINES Filed Jan. 10, 1950 2 Sheets-Sheet l Inventor A umni, flfim A/ July 17, 1951 A. M. BROWN 2,561,175

YARN FEEDING MECHANISM FOR KNITTING MACHINES Filed Jan. 10, 1950 2 Sheets-Sheet 2 I n venior 9/5552" If. 5170M yarn compensator.

Patented July 17, 1951 YARN FEEDING MECHANISM FOR KNITTING MACHINES Albert Matthews Brown, Leicester, England, as-

signor to G. Stibbe & Co. Limited, Leicester, England, a British company Application January 10, 1950, Serial No. 137,868 In Great Britain January 27, 1949 This invention relates to yarn feeding mechanism for knitting machines, and has reference particularly to such mechanism of the type comprising means capable of drawing-off the yarn from its supply at varying rates on its way to the needles, and adapted to determined these rates in accordance with variation in the tension of the yarn.

Mechanism of the type concerned embodies a positively driven component or components with guides for the yarn and is adapted to be iniiuenced by variations in tension of the yarn during knitting, whereby, as the result of such variations, the position of the running yarn is varied lengthwise of the drawing-off component or components and the rate at which the yarn is drawn from the supply is correspondingly varied, as occasion demands.

The rocking member is, in effect, and will hereinafter be referred to in the following further description and in the appended claims as, a yarn compensator. The portion of the running yarn passing to the needles extends through a guide fitted to an upwardly directed arm on the yarn compensator. Accordingly, variations in the tension of the yarn resulting from the knitting action produce rocking movements of the Depending radially from the yarn compensator towards the drawing-off component or components, e. g. normally to a point substantially midway between the ends of the latter, is a further wire provided with a guide, or

closely adjacent guides, through which the yarn ispassed immediately in advance of the yarn drawing-01f component or components. Consequently, on rocking of the yarn compensator, according to variations in the tension of the yarn, the last mentioned guide or guides shifts or shift the yarn axially along the positively driven drawing-01f component or components one way or the other to eifect, as hereinbefore mentioned, a corresponding variation in the rate of drawing-off.

Now heretofore, a yarn compensator of this character has customarily comprised a container divided into compartments with communicating openings, and a quantity of mercury placed in 8 Claims. (Cl. 66-132) vide, in or for a yarn feeding mechanism of the type herein referred to, an improved yarn compensator of a particularly simple, compact and relatively light form designed to dispense with the use of mercury.

The improved yarn compensator constituting this invention has combined therewith a damping l adapted to exert a drawing-off action on the yarn,

the compartments, the whole being so constructed effect under changes in the tension of the yarn.

.The present invention has for its object to prodevice comprising parts movable with and fixed in relation to the compensator respectively, the said parts being so formed, arranged and operable conjointly as to be adapted to damp the oscillations of the compensator and thereby counteract any pendulum effect under changes in the tension of the yarn.

The accompanying drawings illustrate a specific constructional example of the improved yarn compensator.

In the drawings,

Figure 1 is a side elevational view of a yarn feeding mechanism incorporating the said yarn compensator and applicable, for example, to a circular knitting machine of the cylinder. and dial type.

' Figure 2 is a general perspective view of the yarn compensator, showing a part thereof removed and separated from the remainder for the sake of convenience in illustration,

Figure 3 is a side elevational View of the compensator with a portion thereof broken away for clarity, and

Figure 4 is a vertical sectional view taken on the line IV-IV of Figure 3.-

Like parts are designated by similar reference characters throughout the drawings.

Referring to the drawings it will be seen that the improved yarn compensator comprises a shallow circular casing l fitted with a correspondingly shaped cover 2. The casing and its cover may advantageously be made of aluminum or a suitable light alloy, or any other appropriate material. For instance, these parts may even be moulded in a plastic. The casing l is arranged to rock about a central spindle 3 which is adapted to be fixed and held from rotation in a stationary bracket 4. Within the casing l is accommodated a damping device comprising a pivoted damping element 5 in the form of a shoe which is mounted upon a fulcrum pin 6 secured in the flat back of the casing, and a fixed disc I which is rigidly secured upon the spindle 3. The pivoted damping shoe 5 is of flat section and lies against the back of the casing as shown more clearly in Figure 4. The operative end 8 of the damping shoe, at one side of the fulcrum pin 6 is inwardly directed and formed with a rounded nose ta disposed to press frictionally upon the periphery of the fixed disc 1 for the purpose of braking or checking the rocking movements of the casing I and thereby damping the oscillations of the yarn compensator as previously explained herein. The tail 9 of the damping shoe 5, at the opposite side of the fulcrum pin 6, is long compared with the relatively short operative end 8 and at its outer end is enlarged as at 10 to provide additional weight. The upper edge of the damping shoe is inwardly curved in such a way that, with the exception of its nose 8a, the shoe avoids contact with the disc 1. The said shoe, moreover, is entirely gravity-controlled, the weight of its enlarged end In urging the tail 9 away from the disc I and consequently tending to turn the nose 8a inwards so as to maintain it in frictional contact, under the appropriate degree of pressure, with the periphery of the disc I.

As to the disc I, this is constituted, in the particular example illustrated, by a circumferential flange formed integrally with a collar ll rigidly secured upon the central spindle 3. As shown in Figure 4, the collar ll functions also as a bearing for the casing I.

The customary wires formed or provided with the yarn guides are riveted upon the outside of the back of the casing I, so as to be located at the side of the yarn compensator nearest to its supporting bracket 4. Thus, a wire I2 extends upwardly and forwardly at an angle from the casing I and is furnished at its upper end with a porcelain (pot) eye l3, whilst the other and shorter wire M depends radially from the casing and is bent at its lower extremity to form n a pair of closely adjacent yarn guiding loops l5 and I6.

To maintain tension on a yarn, such as y running through the loops I5 and I6 and the eye I3 to the needles [1 and (see Figure 1), the casing l is suitably counterweighted by the attachment to the outside thereof of a counterweight I9.

The cover 2 serving to close the casing and thus completely encase the hereinbefore described damping device is peripherally flanged at 20 to embrace the wall 2| of the casing. In the centre of the cover is formed a hole through which the outer end of the spindle 3 projects. When applied, the cover 2 is held in position by a spring clip 22. At one end this clip is secured, e. g. by a rivet, to the back of the easing I, the clip being bent to extend first laterally across and adjacent to the wall of the casing and then radially inwards in front of the cover 2 where it impinges on and grips the latter. Tothe inside of the cover is secured a further weight 23 the position of which in relation of the counterweight l9 can be varied by turning the cover about the casing. The construction and arrangement are therefore such that by turning the cover to different angular extents relatively to the casing, the weight 23 can be caused to counteract the effect of the counterweight I!) to varying degrees, thereby commensurately varying the tension on the running yarn. For the purpose of accurately determining the tension of the yarn, the free end of the spring clip 22 is made pointed thereby enabling it to function additionally as an indicator for use in conjunction with calibrations on the edge of the cover 2. Conveniently, and as shown, the said cover is circumferentially "bevelled at the junction between its face and I8 of the machine" its inwardly directed peripheral flange 20 and an appropriate arcuate portion of this bevel is serrated or equivalently formed to provide pointed calibrations 24 which may, if desired, be suitably numbered to guide an operator when turning the cover to vary the position of the weight 23.

The use of the herein described yarn compensator economises space, so that considerable numbers of the compensator-s can without any difiiculty be disposed around a large multi-feeder knitting machine.

The improved yarn compensator is relatively inexpensive to produce, and may be used in conjunction with yarn furnishing means of the known type comprising a pair of frusto-conical toothed wheels, arranged with their axes parallel, and their teeth in mesh, so as to be adapted to measure ofl' variable lengths of yarn according to the different points along the wheels at which yarn passes between them, as determined by the yarn compensaton, It is, however, prin-' cipally the intention to use the improved yarn compensator in combination with a yarn feeding mechanism of the character described in United States Patent No. 2,537,000 granted January 2, 1951, that is to say mechanism embodying a single positively driven tapered roller such as that indicated at 25 in Figure l and about the periphery of which the yarn y is intended to be lapped or wrapped on its way to the eeder of the machine.

In Figure 1, the reference numeral 26 indicates a bobbin from which the yarn y is being drawn. From this bobbin the yarn extends first upwardly through tensioning discs and yarn guides not shown) at the top of the superstructure of the knitting machine from whence it extends downward through a pot eye 21 fixed in the bracket 4. From this .bracket, the yarn extends down through the loop I5, around the tapered roller 25, then through the loop l6, downwardly again and through a dropper guide 28 which is incorporated in a stop motion, and then upwardly through the eye l3. After passing horizontally and around a further guide 29,.the yarn y finally extends downwards through a feeder bracket 30 to the needles.

What I claim then is:

1. In yarn feeding mechanism of the type herein referred to for a knitting machine, a yarn compensator comprising, in combination, a central fixed spindle, a member arranged to rock about the said spindle, an upwardly directed arm on the said member which arm is provided with a guide for a running yarn, a second arm which depends from the rocking member and is provided with at least one further uide for the said yarn, a disc fixed on the spindle, and a damping element which is mounted on the said rocking member and adapted for co-operation with the fixed disc in such a way as to damp the oscillations of the rocking member and thereby counteract any pendulum efiect thereof under changes in the tension of the yarn running through the aforesaid yarn guides.

2. A yarn compensator according to claim 1, wherein the damping element is adapted to press frictionally upon the fixed disc.

3. In yarn feeding mechanism of the type herein referred to for a knitting machine, ayarn compensator comprising, in combination, a central fixed spindle, a member arranged to rock about the said spindle, an upwardly directed arm on the said member which arm is provided with a guide for a running yarn, a. second arm which depends from the rocking member and is provided with at least one further guide for the said yarn, a disc fixed on the spindle, and a damping element which is in the form of a shoe fulcrumed on the rocking member, the said element being adapted to press frictionally upon the relatively fixed disc so as to damp the oscillations of the rocking member and thereby counteract any pendulum eflect thereof under changes in the tension of the yarn running through the aforesaid yam guides.

4. In yarn feeding mechanism of the type herein referred to for a knitting machine, a yarn compensator comprising, in combination, a central fixed spindle, a member arranged to rock about the said spindle, an upwardly directed arm l on the said member which arm is provided with a guide for a running yarn, a second arm which depends from the rocking member and is provided with at least one further guide for the said yarn, a disc fixed on the spindle, and a damping element in the form of a shoe fulcrumed upon the rocking member, the operative end of the damping element at one side of the fulcrum being adapted for contact frictionally with the periphery of the fixed disc, and the tail of the said element at the opposite side of the fulcrum being so loaded as to be urged away from the disc so as to turn the aforesaid operative end inwardly and maintain the frictional contact whereby the oscillations of the rocking member are damped, for the purpose herein described.

5. In a yarn feeding mechanism of the type herein referred to for a knitting machine, a yarn compensator comprising, in combination, a central spindle, a casing arranged to rock about the said spindle, an upwardly directed arm which is attached to the said casing and provided with a guide for a running yarn, a second arm which depends from the casin and is provided with at least one further guide for the said yarn, and, accommodated within the casing, a damping device consisting of parts movable with the casing and fixed, respectively, the said parts being ar- 4 ranged in frictional contact so as to damp the oscillations of the casing and counteract any pendulum eil'ect thereof under changes in the tension of the yarn running through the afore said yarn guides.

6. In a yarn feeding mechanism of the type herein referred to for a knitting machine, a yarn compensator comprising, in combination, a central spindle, a casing arranged to rock about the said spindle, an upwardly directed arm which is attached to the said casing and provided with a guide for a running yarn, a second arm which depends from the casing and is provided with at least one further guide for the said yarn, a damping device accommodated with the casing, the said device consisting of parts movable with the casing and fixed, respectively and the said parts being arranged in frictional contact so as to damp the oscillations of the casing and counteract any pendulum eiIect thereof under changes in the tension of the yarn running through the aforesaid yarn guides, a counterweight attached to the casing, and an additional weight mounted on the casing and the, position of said weight being variable to counteract the effect of the counterweight to varying degrees and so commensurately vary the tension on a running yarn.

7. A yarn compensator according to claim 6, wherein the casing is provided with a cover to which the additional weight is attached, the construction enabling the effect of the counterweight to be counteracted to varying degrees by turning the cover to different angular extents relatively to the casing.

8. A yarn compensator according to claim '1, wherein the cover is held in position on the casing by a spring clip a portion of which also functions as an indicator to assist in turning the cover to a required extent.

ALIBERT MATTHEWS BROWN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,562,829 Howie Nov. 24, 1925 1,594,958 Howie Aug. 3, 1926 2,537,000 Stibbe et al. Jan. 2, 1951 

